Anionic complexes of monomeric emulsion stabilizers

ABSTRACT

Anionic complexes of quaternary ammonium salts having an ethylenically-unsaturated radical and a lipophilic radical covalently linked to the quaternary nitrogen atom are disclosed. These anionic complexes are useful as monomeric emulsion stabilizers.

United States Patent 11 1 Samoinr 1111 3,759,982 1451 Sept. 18,1973

1 ANIONIC COMPLEXES OF MONOMERIC EMULSION STABILIZERS [75] Inventor:Carlos M. Sam our, Wellesley, Mass.

[73] Assignee: The Kendall Company, Walpole,

Mass.

22 Filed: May 26,1970

21 Appl. No.: 40,705

[52] US. Cl. 260/485 J, 117/161 UZ, 260/29.6 TA, 260/29.6 SQ, 260/29.6HN, 260/79.3 M,

260/80.71, 260/85.5 ES, 260/85.5 AM,

260/482 P, 260/4851-1, 260/486 R, 260/486 H, 260/501.l2, 260/501.13,260/501.15, 260/924 [51] Int. Cl. C07c 69/40 v Primary Examiner-LorraineA. Weinberger Assistant Examiner-E. Jane Skelly Attorney-Ellen P.Trevors and Robert D. Cliodera 57 ABSTRACT Anionic complexes ofquaternary ammonium salts having' an ethylenically-un'saturated radicaland a lipophilic radical covalently linked to the quaternary nitrogenatom are disclosed. These anionic complexes are useful as monomericemulsion stabilizers.

3 Claims, No Drawings 1 ANIONIC COMPLEXES OF MONOMERIC EMULSIONSTABILIZERS This invention relates to anionic complexes of selectedquaternary ammonium salts, and preferably to anionic complexescontaining an ethylenically unsaturated group and two lipophilicradicals.

Polymeric latices, derived from ethylenically unsaturated monomers, arewidely used for a variety of applications, such as adhesive masses andbinders for nonwoven fabrics. Most conventional polymeric latices areproduced by an emulsion polymerization process, in which monomericmaterials are polymerized while they are dispersed in an aqueous mediumby means of a surface active agent. The surface active agent may beanionic in nature, such as soap or sodium lauryl sulfate. Alternatively,it may be of a nonionic type as represented by various ethylene oxidederivatives, or by polyhydroxy compounds, or it may be cationic, asrepresented by alkyl ammonium halides. Cationic agents are preferablycombined with a nonionic agent for improved performance. Thepolymerization of monomeric materials is also frequently effected in thepresence of water-soluble protective colloids or stabilizing agents. Anyof the above emulsifying or stabilizing agents leads to the presence ofa water-sensitive ingredient in the final polymeric latex. For latexutilizations wherein wet strength and resistance to the influence ofwater are desirable, as in most paper coatings, nonwoven fabrics,certain pressure-sensitive adhesive tapes, and the like, the presence ofa water-sensitive ingredient in the polymeric mass is undesirable. Apreferred method of avoiding the presence of water-sensitive elements ina polymeric latex is to employ what is termed herein monomeric emulsionstabilizers that is, a class of organic monomer which copolymerizes withthe ethylenically unsaturated monomers, becoming a part of the finalpolymer, but which stabilizes the polymerization process against theformation of coagulum and against subsequent phase separation. Suchmonomeric emulsion stabilizers may be cationically charged nitrogencompounds as set forth in US. Pat. No. 3,399,159 wherein the use ofmonomers such as vinyl pyridines, acid-amines, and certainnitrogen-containing acrylic derivatives is described.

Now it has been found that anionic complexes of selected quaternaryammonium salts are useful monomeric emulsion stabilizers for thepolymerization of ethylenically-unsaturated monomers.

More particularly, the compounds of this invention have the formulawherein V is an ethylenically-unsaturated radical; A'is zero or adiradical; R, and R are independently selected alkyl, hydroxyalkyl,aryl, R,,O-C-CH or R -NH-CO-CH wherein R is hydrogen or alkyl, ortogether part of a heterocyclic amino radical in which the quaternarynitrogen atom in formula I is part of the ring; R is a lipophilicradical comprising an aliphatic hydrocarbon group having about eight toabout 28 carbon atoms; X is alkyl sulfate wherein the alkyl moiety hasseven to 28 carbon atoms, alkyl benzene sulfonate wherein the alkylmoiety has seven to 12 carbon atoms, phenoxy (or alkyl phenoxy) alkylene(or polyalkyleneoxy alkylene) sulfate having the formula R"C H OCH -CHR"-O-,.CH -CHR" SOfwherein R" is hydrogen or alkyl having one to 12 carbonatoms, R' is hydrogen or methyl and n is zero or an integer, dialkylsulfosuccinate wherein the alkyl groups have one to 24 carbon atoms oralkyl phosphate wherein the alkyl group has one to 18 carbon atoms.

While any compound having the general formula I can be providedaccording to this invention, preferred monomeric emulsion stabilizersinclude those compounds l wherein V is an ethylenically unsaturatedradical selected from the group consisting of acryloyloxy,methacryloyloxy, acrylamido, methacrylamido, vinyloxy, allyloxy,methallyloxy, vinylacetoxy, allylacetoxy, methallylacetoxy, allyl,methallyl, 4-hydroxymaleoyloxy, 4-hydroxyfumaroyloxy, 4-hydroxymaleoylamino, 4-hydroxyfumaroylamino, 4hydroxycitraconyloxy,4-hydroxycitraconylamino, 4- hydroxyitaconyloxy and4hydroxyitaconylamino; A is ethylene, propylene, isopropylene,2-hydroxypropylene, acetoxypropylene or -O-CH CHR (O-CH CHR where n iszero to four and R is hydrogen or methyl with the proviso that A is zerowhere V is vinylacetoxy, allylacetoxy, methallylacetoxy, allyl ormethallyl; R, and R, are independently selected from the groupconsisting of alkyl having one to seven carbon atoms, hydroxyalkylhaving one to seven carbon atoms, benzyl, R,,O--- COCH, and R,,-NH'GOCHwhere R is hydrogen or alkyl having'one to four carbon atoms; ortogether part of a morpholinium or piperidinium moiety; and R and X areas previously described.

By the term lipophilic radical in the claims and specification herein ismeant a radical containing an aliphatic hydrocarbon chain having fromabout eight to about 28 carbon atoms, and preferably from about nine toabout 18 carbon atoms, including saturated, unsaturated, straight-chainand branched groups. This aliphatic hydrocarbon chain can be covalentlylinked to the nitrogen either directly or through an intermediatelinkage as illustrated below where L represents the ali phatichydrocarbon chain: a benzyl group,

an ester or amide group such as --CH CH- R'-ACOL wherein R is hydrogenor methyl and A is oxygen or ---NH---; a polyalkylene oxide group suchas CH,CH- R (OCH,-CHR ),,--OL wherein. R is hydrogen or methyl and n iszero to four;

an acetoxy or acetamido group such as CH- 'alkylene ethers such as -CHOL and ---Cl l ,CHR,,),, where R is hydrogen or methyl and n is zero tofour, and A is oxygen or NH; and isomers of the aforementionedhydroxysuccinyloxy or hydroxysuccinylamino groups wherein the aliphatichydrocarbon chain L is attached to the carbon atom adjacent to thecarboxyl group.

The anionic complexes having the formula I are readily prepared from thecorresponding quaternary ammonium halides. Methods for synthesizing thelatter compounds are fully described in copending U.S. Pat. applicationsSer. No. 867,899, and Ser. No. 867,900 filed Oct. 20, 1969, and theseapplications are incorporated by reference herein.

Thus,'the appropriate quaternary ammonium halide is reacted with analkali metal or ammonium salt such as an alkali metal alkyl sulfate, analkali metal alkyl benzene sulfonate, an ammonium phenoxy (or alkylphenoxy) alkylene (or polyalkyleneoxy alkylene) sulfate, an alkali metaldialkyl sulfosuceinate or an alkali metal alkyl phosphate.Exemplificative salts include sodium heptyl sulfate, sodium iso-octylsulfate, sodium oleoyl sulfate, sodium octacosyl sulfate, sodium dodecylbenzene sulfonate, di-tetradecyl sodium sulfosuccinate, dimethyl sodiumsulfosuccinate, sodium dimethyl phosphate, sodium octadecyl phosphate,sodium di-2-ethyl hexyl phosphate, etc.

The reaction to provide compounds 1 is readily carried out at roomtemperature, although higher and lower temperatures can be employed.

Although the reactions proceed readily in the absence of a solvent,diluents such as water, acetonitrile, dimethylformamide, ethyl acetate,methanol and methylene chloride can be suitably employed. Monomers suchas acrylonitrile and ethyl acrylate can also be utilized as solvents inthe preparation of the monomeric emulsion stabilizers. While compounds 1can be isolated prior to use in polymerization reactions, preferablythey are used in their reaction solutions.

As previously indicated, particularly preferred monomeric emulsionstabilizers are those having two lipophilic radicals, viz, compoundshaving the formula 1 wherein X is alkyl sulfate wherein the alkyl grouphas seven to 28 carbon atoms, alkyl benzene sulfonate wherein the alkylgroup has seven to 12 carbon atoms, dialkyl sulfosuccinate wherein thealkyl groups have seven to 24 carbon atoms, dialkyl phosphate whereinthe alkyl groups have seven to 18 carbon atoms, or R"--C H,OCH,-CHR"'O-,,Cl-l,-CHR"' S is alkyl having seven to 12 carbon atoms, R ishydrogen or methyl and n is zero or an integer. It is preferable tosynthesize these compounds in an aqueous solution, and use them asmonomeric emulsion stabilizers in their reaction solutions withoutremoving the halide salt by-products.

Illustrative ethylenically-unsaturated monomers suitable forcopolymerizing with the monomeric emulsion stabilizers of this inventioncomprise vinyl acetate, vinyl chloride, acrylonitrile, and acrylicmonomers in general represented by the formula where R is a hydrogenatom or a methyl group, and R is an alkyl radical of one to 14, andpreferably one to four carbon atoms. As is known in the art of preparingacrylic ester polymers, the softness of the polymer and the difficultyof initiating polymerization increase as the number of carbon atoms inthe ester group increases. In the practice of this invention, when theacrylic monomer contains more than eight carbon atoms in the estergroup, it is advantageous to mix therewith at least about 20 molepercent of an acrylic ester with fewer than four carbon atoms in theester group to initiate polymerization and enhance the stability of thedispersion.

Mixtures of more than one such ethylenically unsaturated monomer may beused, and in order to impart special properties of toughness, rigidity,or crosslinking reactivity to the polymer, a minor proportion, usuallyless than 20 mole percent, of the major monomer may be replaced by someother ethylenically unsaturated monomer such as vinyl esters, typiliedby vinyl laurate and vinyl stearate; vinyl ethers such as vinyl methylether, vinyl ethyl ether, and vinyl butyl ether; diunsaturated monomerssuch as diethylene glycol diacrylate, ethylene glycol diitaconate,diallyl phthalate, divinyl benzene and the like; acrylic and methacrylicacids, acrylamide and methacrylamide, hydroxyethyl acrylate andmethacrylate, and hydroxypropyl acrylate and methacrylate, and styrene.

In general, in the polymerization process of this invention, 0.1 to 10percent by weight of monomeric emulsion stabilizer is employed, with lto 5 percent by weight being preferred. The amount of monomeric emulsionstabilizer is based on the total monomers added to the polymerizationreaction.

Aqueous polymeric dispersions may be prepared according to thisinvention in which the solid polymer content is 40 percent to 50 percentby weight. If desired, the solids content may be diluted to 1 percent byweight or less, with excellent retention of stability at both the higherand lower concentrations.

The monomeric emulsion stabilizers of this invention are useful in bothbatch and continuous polymerization processes.

The following examples will serve to illustrate the practice of thisinvention.

EXAMPLE 1 Allyl hexadecyl dimethyl ammonium chloride was prepared byreacting allyl chloride with dimethyl hexadecyl amine as described incopending U.S. Pat. application Ser. No. 867,899. The amount of 15.1g.of allyl hexadecyl dimethyl ammonium chloride aqueous solution (23.5percent by weight of the chloride) and 2.88g. dodecyl sodium sulfate wastumbled in 50g. water for 48 hours at room temperature to provide allylhexadecyl dimethyl ammonium dodecyl sulfate.

The amount of 22.5g. of this monomeric emulsion stabilizer solution in275g. water was charged to a 4- neck resin kettle equipped with athermometer, stirrer, nitrogen inlet and dropping apparatus. To thissolution was added, under nitrogen, g. vinyl acetate; the pH of theresulting emulsion was 4.5. After cooling to 19C, 10ml of 3% 11,0 in H Owere added to the emulsion followed by the dropwise addition of areductant solution comprising 0.02g. ferrous ammonium sulfate and 0.4g.ascorbic acid in 10ml H O. Polymerization was initiated after 0.8ml ofreductant solution had been added as evidenced by an exotherm of about28 in 10 minutes. A total of 10ml of reductant solution and 15ml of H 0solution was added until completion of the polymerization as evidencedby a lack of exotherm upon the further addition of a slight amount of H0 and rcductant solution. The yield of polymer was 89 percent oftheoretical and no coagulum formed.

EXAMPLE 2 Ally] hexadecyl dimethyl ammonium chloride (35.5g.) in 115.5g.water were tumbled with 35.8g. sodium dodecylbenzene sulfonate at roomtemperature for 24 hours. The resulting solution was extracted withhexane, and the hexane layer dried over anhydrous sodium sulfate. Afterremoval of solvent under vacuum, a gummy yellow solid, identified asallyl hexadecyl dimethyl ammonium dodecylbenzene sulfonate, wasobtained.

Following the procedure of Example 1, a mixture of ethyl acrylate(80g.), butyl acrylate (g.) and acrylonitrile (10g) in water (280g) wasemulsified using 3g. of the allyl hexadecyl dimethyl ammonium benzenesulfonate. The pH of the initial emulsion was about 5.0-5.5. Aftercooling to 17C, 10ml of 3% H O, in H O was added, followed by thedropwise addition of the reductant solution described in Example 1. Atotal of 4ml of reductant solution and 1 lml of H 0 solution wasemployed in the polymerization.

EXAMPLE 3 Allyl dimethyl dodecenyl hydroxysuccinyloxyethyl ammoniumchloride was prepared by reacting allyl chloride with dimethyl aminoethanol in acetonitrile, followed by reaction with dodecenyl succinicanhydride in acetonitrile as described in copending patent applicationU.S. Ser. No. 867,900. The amount of 43.2g. of this compound was tumbledwith 32.2g. sodium dodecylbenzene sulfonate in 300ml acetonitrile for 24hours at room temperature. The resulting precipitate was removed byfiltration, washed with acetonitrile and dried. Removal of theacetonitrile provided 64.5g. of allyl dimethyl dodecenylhydroxysuccinyloxyethyl ammonium dodecylbenzene sulfonate.

A mixture of ethyl acrylate (280g), acrylonitrile (35g) and butylacrylate (35g) in 843g. of H 0 was emulsified employing 157g. of anaqueous solution containing 10.5g. of the allyl dimethyl dodecenylhydroxysuccinyloxyethyl ammonium chloride. The pH of the initialemulsion was about 4.5. After cooling to 16C, 35ml of 3% H 0 in H O wasadded, followed by the dropwise addition of the reductant solutiondescribed in the previous examples. Polymerization was initiated uponthe addition of 15ml of reductant solution.

What is claimed is:

l. A compound having the formula wherein V is allyl or methallyl, A is adirect linkage, R

and R are independently selected alkyl having one to seven carbon atoms,R, is -R-,-OCOCHLCH- -COOH or R OCO-CH -CHLCO0H wherein R, is ethylene,propylene or isopropylene and L is an aliphatic hydrocarbon chain havingfrom about eight to about 28 carbon atoms, and X is an alkyl benzenesulfonate wherein the alkyl moiety has seven to 12 carbon atoms.

2. A compound having the formula I

2. A compound having the formula
 3. The compound of claim 2 having thename N-allyl, N,N-dimethyl, N-(dodecenyl hydroxysuccinyloxy ethyl)ammonium dodecyl benzene sulfonate.